Driver assistance systems are known, which assist a driver when assessing a passing process. The publication DE 36 22 447 C1, for example, teaches a device for displaying passing recommendations. Vehicles to pass and oncoming vehicles are located by means of a radar unit and it is ascertained from these vehicles and from variables associated with the host vehicle whether a passing process with or without additional acceleration is or is not possible. A maximum available passing lane is ascertained from the data of the oncoming vehicles. If there are no oncoming vehicles, the range of the radar device is assumed to be an available path for passing.
The problem in this case is that in some driving situations, the driver is displayed an possibility to pass when in fact a passing process should not be carried out.